In testing the fluorescent compound, the team observed a difference in the intensity of the fluorescence between the drinks containing GHB and those without (Photo: National University of Singapore)

Central to the dangers of so-called "date-rape" drugs is the fact that they are difficult to detect. Indeed, GHB, one of the most commonly-used of such drugs, is both colorless and odorless. A team of researchers from the National University of Singapore (NUS) has developed a fluorescent sensor which, when mixed with a drink containing GHB, changes color within 30 seconds, potentially alerting people soon after their drink has been tampered with.

The researchers sought to explore the effectiveness of fluorescent dyes in the realm of drug detection, citing their high sensitivity, fast response time and technical simplicity as characteristics that could help break new ground in the area.

Working through a short-list of 17 compounds, the team, led by Professor Chang Young-Tae of the Department of Chemistry at the NUS Faculty of Science, identified an orange compound that changed color when mixed with GHB, aptly dubbing it "GHB Orange."

To determine the efficiency of GHB Orange, the team set about testing how it reacted to the drug when mixed into different drinks ranging from alcoholic to non-alcoholic and colored to non-colored.

The team observed a difference in the fluorescence intensity between the drinks containing GHB and those without. While in the lighter-colored or translucent drinks, the change in color was visible to the naked eye, extra light was required to observe the change in darker drinks, such as cola or whiskey.

Researchers at various institutions have previously produced sensors that react to GHB and other commonly used date-rape drugs, but integrating the materials into convenient and viable products has proven a challenge in itself. Researchers from Tel Aviv University have looked to develop a pocket-sized drug detecting sensor, while the company DrinkSavvy is using plastic cups and straws to alert would-be drink spiking victims to anything untoward.

It is unclear at this stage exactly what form GHB Orange could take in terms of a commercial product, but the team is now planning to work with industry partners to develop a cheap and practical device for detecting GHB.